浅析Android Handler的使用误区与避免

Android程序中一些耗时的操作如从网络上下载一些文件或读取一些数据等操作不能放到主线程(也就是UI线程)中执行,而是要启动一个子线程进行处理。Android提供了一个Handler类来解决此问题,但Handler在使用上存在一些误区。本文通过例子程序浅析了Handler使用的误区所在,并且提出了避免此误区的必要做法。

Teamcenter中基于Handler的文件审签技术的研究

阐述了Teamcenter系统中工作流程和处理程序(Handler)扩展工作流程(workflow)的技术,研究了基于Handler的文件审签技术,给出Handler的应用实例,实现技术文件审签信息的自动填入,最终成功验证了基于Handler的文件审签技术的可行性。

网络通信框架Handler

本文介绍了网络通信框架Handler,Handler主要接受子线程发送的数据, 并用此数据配合主线程更新UI。本文设计一个实例重点论述开发过程的设计及实现,是移动开发的一个典型实例。

Android Handler消息传递机制在人机界面软件设计中的应用

Handler消息传递机制作为Android平台的一种"事件处理"方式,被广泛应用在Android软件多线程之间的数据交换。为了实现Android平台烟尘自动测控仪人机界面软件实时获取采样数据并更新软件界面,文中使用Android系统的Handler消息传递机制,将采样数据接收进程的数据包装成Bundler类传递给软件的主线程,由主线程解析数据并更新软件界面。实验结果表明,使用Android平台Handler消息传递机制可以准确实现软件中多个线程的通信,实时更新软件界面。

基于Handler的WebService访问控制的实现

本文深入研究了WebService SOAP消息规范和包含的多种技术,提出了利用WebService服务器的Session 管理和WebService的Handler技术实现WebService访问控制,并在实际项目实施中得以应用。

Food Hygiene Knowledge, Attitudes and Practices of the Food Handlers in the Military Hospitals

Improper practices and lack of knowledge by food handlers are contributing factors for the spread of foodborne outbreaks. This study aimed to explore the knowledge, attitude and practice of food handlers in military hospitals in Jordan. A Self completed questionnaire was answered by 200 employees;150 military employees and 50 civilian employees in 7 Jordanian military hospitals selected randomly one from the capital Amman and two from the three provinces. The results showed that the means of the percentage scores for the knowledge, attitude, practice, were 84.82, 88.88, 89.43, respectively and the overall knowledge, attitude, practice (KAP) mean percentage score was 87.88. A significant difference (P 0.05) in these values was observed between the military and civilian employee. The mean percentage scores for knowledge, attitude and practice were 88.5, 93.2, and 91.4, respectively for military employee compared to those for civilian employee of 73.7, 75.8, and 83.5, respectively. A significant difference for the overall (KAP) mean percentage score was also observed between gender, education and specific occupation of the food handler. Female KAP percentage mean score was 90.0 and that for males was 86.6;The college or university educations employee had a mean score of 91.6 while the elementary school education employee had a mean score of 79.7;The nutritionists and cooks had statistically similar means of 91.6 but these occupations significantly differ from the waiters 84.4 and cleaners 80.2.

Cross Sectional Study of Skin Carriage and Enterotoxigenicity of Staphylococcus aureus among Food Handlers

The prevalence of enterotoxigenic Staphylococcus aureus was investigated among 200 participants working in three different food processing plants in Egypt. Using skin swabs, 75 (38%) of the 200 tested persons were positive for the presence of S. aureus. Of the S. aureus positive persons, 28 (14%) harboured S. aureus produced staphylococcal enterotoxins. The serotypes of these enterotoxins were enterotoxin A (68%), enterotoxin B (36%), enterotoxin C (46%) and enterotoxin D (18%). Some of these isolates produced more than one type of enterotoxins namely AB, AC, BC, BD, ABC and ACD. Analysis of risk factors implicated in skin carriage of S. aureus as age, gender, marital status, education, duration in employment, frequency and method of hand wash and incidence of chronic skin infection revealed insignificant association with staphylococcal skin carriage. The obtained results put forth the risk of food contracting contamination with enterotoxigenic strains of S. aureus owing to skin colonization of S. aureus among food handlers.

Survey of food handlers in bukas (a type of local restaurant) in Lagos, Nigeria about typhoid fever

Purpose: The study was conducted to survey the knowledge and behavioural practices of food handlers in bukas (a type of local restaurant) in Nigeria with the aim of assessing the hygiene practices of food handlers and whether they were knowledgeable about typhoid fever and its mode of transmission. Methods: One hundred and seventy four (174) Respondents were ad- ministered questionnaires on their sociode- mographic characteristics, behavioural practices and knowledge of typhoid fever. Results: Ma- jority of the food handlers drank pure water (32.1%), borehole water (32.6%) and public tap water (31.1%) at the about the same frequecy. More than half (62.2%) washed their hands with water only before eating while 27.7% did not wash their hands always before preparing food. After using toilets, 71.9% washed their hands with soap and water while 28.1% washed their hands with only water. When asked if they had heard about typhoid fever 90% said they had heard, out of which15.6% did not know how it was contracted while the others had partial knowledge. Conclusion: Food handlers play a prominent role in the transmission of typhoid fever and so it is important that the food handlers are well informed about their hygiene status and the causes of typhoid fever trans- mission and ways by which typhoid fever spread is prevented. This will go a long way to help reduce the incidence of typhoid fever in the country.

Social and Personal Determining Factors in the Results on Contents of Food Handlers’ Formation Plans

This study has two main objectives: on one hand, the evaluation of food items related to the food training courses in order to know which ones require better explanations from trainers and a further development and refinement by food handlers. It is also a goal of this work to appreciate the level of general knowledge of food handlers before receive any training session and then see if there was some improvement after the course. On the other hand, identifying potential social and personal factors of food handlers that influence on the results of the evaluation. To this end, two tests were performed (one before the training and at the end) and evaluated the results per modules. In general, knowledge levels both initially and after taking the course proved to be satisfactory. Personal and social factors determined better or worse scores on the basis of these.

Evaluation of Food Hygiene Knowledge Attitudes and Practices of Food Handlers in Food Businesses in Accra, Ghana

Food handlers have a prime role to play in food businesses, and that is to guarantee that meals served are hygienic for consumption. Conscious or inadvertent contamination of such food places consumers at risk of suffering from food- borne illnesses. For this reason the study was carried out to document the food hygiene knowledge, attitudes and practices of some food handlers, in food businesses in Accra, Ghana and also to determine the microbiological load of the foods sold by the food businesses. The study targeted food handlers in the hotel industry. The study involved a field survey, followed by a laboratory assessment of microbiological status of food samples obtained from the sampled hotels. Cross tabulations and chi – squared tests (5% significance level) as well as frequency distributions were used to analyze the data obtained from the field survey. Data obtained from the laboratory assessment were also compared to standard values of microbiological counts. Majority of respondents were between the ages of 30 - 40 years (42.9%) with tertiary or post secondary education. Food hygiene knowledge and attitudes were satisfactory, however its practice was challenging. Gender, age and educational level of respondents did not influence their food hygiene practices. Microbial counts of all food samples was generally high ranging from 1.2 × 105 CFU/g to 1.1 × 108 CFU /g. The total coliform counts of foods ranged from 1.0 × 104 CFU/g to 5.0 × 106 CFU/g, and these were obtained from three out of the five hotel kitchens sampled. The study concluded that, the food hygiene knowledge and attitudes of the food handlers did not result in efficient food hygiene practices.

A Campylobacteriosis Outbreak Caused by One Asymptomatic Food Handler Carrier

In August 2021,three students with diarrhea from the same school visited a local hospital in the S district of Beijing.An epidemic investigation showed that there were more students with diarrhea in the same school and they had one meal together.Campylobacter jejuni was isolated from both patients with diarrhea and asymptomatic food handlers;however,the latter also carried Campylobacter coli.Phylogenomic analysis showed that there was a campylobacteriosis outbreak among the students,and the asymptomatic food handler may have been the source of the infection.Routine inspection and surveillance for Campylobacter is needed for the food producing staff,particularly those cooking in the cafeteria in schools or other public food services.

Knowledge Level and Self-Reported Attitudes of Food Handlers: Case Study of a University Campus

This study was performed conducting surveys to assess the Knowledge Level (KL) and Self-Reported Attitudes (SRA) of Food Handlers (FH) in order to evaluate their food safety perception. Food handlers working in 5 cafes and 6 canteens in a university campus responded to a questionnaire about food hygiene. The knowledge level about food hygiene was obtained by answering five question groups (G): Agents involved in food borne diseases (G1), Food handling hygiene (G2), Cross contamination (G3), Heat treatment/cooling techniques (G4), Reduced temperatures (G5). The SRA level was obtained through seven questions with multiple choice options on behaviors of health and safety applied to the work routine, which were considered as percentage of hits. The hygiene’s knowledge average was 75%, ranging from 63.3% (G4) to 94.5% (G3). Significant associations between establishment type and G1 (p = 0.027), professional experience and G5 (p = 0.020), training and G5 (p = 0.037) were found. Food handlers knowledge did not have effect in FH attitude (p = 0.371). From 25 FH (46.0%) who had high KL, 17 had reported incorrect attitudes. The level of hits is, in general, more than 75%, except for matters relating to the use of different cutting tables (44.4%) and knives (51.9%). Significant differences of values and odds for handlers’ knowledge were observed between cafes’ and canteens’ FH. No difference (p > 0.05) was observed in FH SRA scores according to the type of establishment. The results reveal a reduced application of knowledge acquired by food handlers, evidenced by the low level of attitudes considered correct. This clearly justifies the implementation of additional measures, including on job training as part of an effective strategy to control establishment’s food safety.

Prevalence of intestinal parasitic infections in certified food-handlers working in food establishments in the City of Nairobi,Kenya

Most intestinal parasites are cosmopolitan with the highest prevalence in the tropics and subtopics. Rural-to-urban migration rapidly increases the number of food eating places in towns and their environs. Some of these eating estabishments have poor sanitation and are overcrowded, facilitating disease transmission, especially through food-handling. Our investigations in Nairobi, therefore, were set to determine the presence of intestinal parasites in food-handlers with valid medical certificates. Direct and concentrated stool processing techniques were used. Chisquare test and ANOVA were used for data analysis. The parasites Ascaris lumbricoides, Entamoeba histolytica and Giardia lamblia were observed in certified food-handlers. Significant difference was found in parasite frequency by eating classes and gender （χ^2 = 9.49, P = 0.73）, （F = 1.495, P = 0.297）, but not in parasite occurrence between age brackets （χ^2 = 6.99, P = 0.039）. The six-month medical certificate validity period may contribute significantly to the presence of intestinal parasites in certified food-handlers.

Food Handler＇s Perception of Fresh Cut Products

The use of Fresh Cut Products （FCP） allows food service units to offer a greater variety of menus, reducing costs and minimizing cross contamination. Few food units in Portugal are adopting FCP, since these products are viewed as being more expensiveand are regarded as less natural and easily perishable.The present study aims to identify and analyze the level of awareness of food service operators in respect to FCP. Approximately 90% of food handlers referred the use of FCP at their workplace, pointing as the main advantages for using them the less time spent on preparation （58.6%）, the variety （55.9%） and the convenience （55.9%）. Reasons for not using them were doubtful origin （91.7%）, price （66.7%） and being a possible threat to their jobs （58.3%）. In spite of recognizing the advantages of using FCP, most of food handlers （77.2%） prefer traditional products. Traditional products were preferred by food handlers with lower educational level, working at schools and performing functions of kitchen helper. FCP were chosen by younger food handlers, with higher educational level. It seems necessary to promote a demystification of this category of products near food service managers and employees, explaining the best way and advantages of using FCP at institutional food services in terms of safety, cost and quality.

A CAWL handler for context-aware composite workflow services

In distributed computing environment,workflow technologies have been continuously developed.Recently,there is an attempt to apply these technologies to context-aware services in ubiquitous computing environment.The middleware,which offers services in such environments,should support the automation services suited for the user using various types of situational information around the user.In this paper,based on context-aware workflow language(CAWL),we propose a CAWL based composite workflow handler for supporting composite workflow services,which can integrate more than two service flows and handle them.The test results shows that the proposed CAWL handler can provide the user with the composite workflow services to cope with various demands on a basis of a scenario document founded on CAWL.

Assessment of Knowledge,Attitudes and Practices of Food Handlers in Attieke Production Units in Relation to Food Hygiene and Safety in Cote d’Ivoire in 2012

The aims of this study were to investigate the food safety knowledge and practices of food handlers and to assess the sanitary conditions of attieke production units in the South of C?te d’Ivoire. A cross-sectional study was conducted during 4 months in 2012 in 7 localities and data were collected using questionnaire and observation checklist and microbiological analysis of hands. A total of 775 attieke production units were involved in this survey. Seventy-one percent (71%) were located on public domains and only 70 production units (9%) used septic tank as a mean of final deposal for liquid waste. Hygiene conditions and practices of food handlers in attieke production units were inadequate. The presence of specific microorganisms such as Staphylococcus aureus, Klebsiella pneumoniae, Enterobacter agglomerans, Citrobacter youngae, Klebsiella oxytoca and Citrobacter freundi was indicative of a degree of ignorance on the part of food handlers towards proper hygienic practices.

基于Axis的Web服务认证模块的设计和实现

WebServices为企业系统集成、电子商务等提供了规范的、开放的分布式应用环境。但现有的安全机制不能满足WebServices体系的安全需求,身份认证是安全问题中的一个基本问题,利用ApacheAxis提供的Han dler机制,设计和实现了一个认证模块,使服务使用者和服务提供者在不对原有代码作任何改变的条件下完成身份认证。

Android多线程与消息循环

消息循环是Android事件处理的基础。本文深入研究了Android的消息循环机制及其相关实现类,比较了Android UI线程与工作线程的消息循环机制的异同,最后通过一个例子说明了线程间通过消息循环进行通信的具体实现。

基于Android平台的智能温控系统设计与实现

随着物联网技术和移动互联网技术的发展,无线传感网以及移动互联网技术正逐渐应用于智能温控系统。阐述了温度控制基本原理,分析并给出了以无线传感网为基础、基于Android平台的智能温控系统设计方案,提出了温度监控的基本业务逻辑处理流程,并利用Android的Handler机制解决温度的实时采集与监控问题。开发设计了基于Android平台的智能温控系统APP程序,并进行了运行和测试。